There are known conventional image-forming devices that adjust images so that there are no deviations in positions or densities of images formed on a recording medium. For example, procedures for adjusting images include: to form a registration pattern in each color to be used for adjusting the image positions; to acquire an amount of offset (a correction value) between the registration pattern formed in a reference color and each of the registrations patterns formed in target colors; and to correct the position of the images in the target colors based on these correction values.
Here, there is a known problem that time required to acquire the correction values may lead to a decline in printing efficiency. To this effect, Japanese patent application publication No. 2001-013753 discloses a technology to reduce copy time by canceling the process to acquire correction values.